Indonesian President Joko Widodo sent his condolences on Monday to the families of the crew aboard a submarine found at the bottom of the sea just one day earlier.
"I send my deepest condolence for the passing of 53 navy members onboard KRI Nanggala-402 who had fallen during an assignment in the waters north of Bali."
In his address to the nation, the president also said the government would pay for the education of the lost crew members' children.
Meanwhile, Indonesians mourn the loss of their friends and family members aboard the submarine.
One victim's uncle said he hopes the crew members’ bodies will be found and returned.
"We'd already given our nephew to the government to serve in the military. Now that he has fallen in the operation, we hope the government will return his remains to us after all the official ceremonies, because each of us has our own religion, like Hinduism."
The Indonesian submarine had lost contact during a weapons drill last week.
The country’s top Navy chief blamed the accident on “forces of nature” and not the crew.
More than a dozen helicopters and ships searched the area where contact was lost with the help of the U.S., Australia, Singapore and Malaysia.
On Sunday, military officials said the submarine had been found broken into at least three parts at the bottom of the Bali Sea.
Indonesia, Southeast Asia's most-populous country, has sought to revamp its military, but its ageing equipment has been the cause of several fatal accidents in recent years.